The invention relates to a device for producing x-y coordinate addresses for a picture screen comprising a force sensitive transparent operating plate influencing force measuring sensors. When a force is exerted on the surface of the operating plate, the force measuring sensors produce at the pressure point electrical signals resulting from a change in the sensor electrical parameters, which are converted in an electronic system into digital x-y coordinate addresses, which accurately correspond to the geographical place of the pressure point on the picture screen. The operating plate has first side edges arranged approximately parallel and opposite to each other and second side edges shifted by about 90.degree. with respect to the first side edges and also arranged approximately parallel and opposite to each other. The operating plate is arranged on resilient edge supports. The mechanical device is mounted in the front frame of a high resolution monitor before the picture tube and is used as a touch panel.
Such a device is known from German patent application No. 3420701. With the operating plate of rectangular shape, the force measuring sensors are arranged at the corners of the plate. It has been found that the coordinates of a point loaded by pressure on the surface of the plate in this case deliver electrical signals corresponding only theoretically to point coordinates. In practice it is found that in a device with the force measuring sensors at the corners of the plate the desired signals are only obtained when a pressure is exerted on the operating plate adjacent the center of the plate.